Rim polyurethane or polyurea compositions containing internal mold release agents

ABSTRACT

The present invention is directed to a process for the production of optionally cellular, polyurethane elastomer moldings or optionally cellular, rigid structural polyurethanes by reacting a reaction mixture containing 
     (i) a polyisocyanate, 
     (ii) a high molecular weight polymer having at least two isocyanate-reactive groups and having a molecular weight of 400 to about 10,000, 
     (iii) about 5 to 50% by weight, based on the weight of component (ii) of a chain-extender having at least two isocyanate-reactive groups and 
     (iv) about 0.05 to 10 weight percent, based on the weight of components (ii) and (iii) of a salt based on a carboxy functional siloxane and an amidine group-containing compound of the formula ##STR1##  wherein R 1 , R 2  and R 3  are straight or branched, saturated or unsaturated hydrocarbon chains having up to 30 carbon atoms which may optionally be substituted by ether groups, ester groups, amide groups or amidine groups and may also optionally be terminated by isocyanate-reactive groups such as hydroxyl or amino groups, 
     R 4  corresponds to the definition of R 1 , R 2  and R 3 , but may additionally represent an aromatic substituent having 6 to 15 carbon atoms or may represent the group --NR 2  R 3  and 
     R 1 , R 2 , R 3  and R 4  may, with one or both of the amidine nitrogens, also form a heterocyclic ring. 
     The present invention is also directed to the amidine group-containing salt (iv) and to a isocyanate-reactive composition based on components (ii), (iii) and (iv).

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a Continuation-in-Part of U.S. applicationSer. No. 006,529, filed on Jan. 23, 1987.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is directed to an internal mold releasecomposition suitable for use in the production of optionally cellular,polyurethane or polyurea elastomers or optionally cellular, rigidstructural polyurethanes or polyureas by the reaction injection molding(RIM) process.

2. Description of the Prior Art

Polyurethanes or polyureas having an impervious outer skin (integralskin) and an optionally cellular core are well known and suitable formany uses. Such polyurethanes and polyureas are generally produced byintroducing a reaction mixture based on polyisocyanates,isocyanate-reactive compounds and other additives into closed molds suchthat the reaction mixture fills the mold and reproduces the innersurface thereof. In order to prevent the molded article from adhering tothe surface when the mold is opened, the mold is generally coated with arelease agent. Examples of release agents currently in use includewaxes, soaps, and oils. These external release agents form a thin filmbetween the surface of the mold and the molded article. This thin filmassists in preventing the molded article from adhering to the mold andthus enables the article to be readily removed from the mold.

This method has a number of disadvantages where mass production isdesired. For instance, the release agent has to be applied at regularintervals, and during that period the mold is out of service. Also, fineengravings on the mold surface such as imitation wood or leather grainbecome covered with residues of release agents over a period of time.The removal of these firmly adhering residues from very complicatedmolds involves considerable time and expense. Further, the moldedarticles are also coated with a thin film of release agent which causesadhesion problems when subsequently painted.

One solution to this problem has been to include a mold release agent inthe reaction mixture so that it is possible to reduce or eliminate theseparate application of an external mold release agent. U.S. Pat. No.4,076,695 discloses the incorporation of carboxy functional siloxanesinto the polyurethane reactants to be used in a reaction injectionmolding process in order to aid the release of the molded article fromthe mold. One difficulty with this approach is that the carboxyfunctional siloxanes react with the tin catalysts conventionally used topromote polyurethane formation resulting in insoluble adducts which nolonger provide mold release properties.

Various solutions have been suggested to overcome this problem. U.S.Pat. No. 4,379,100 discloses a three stream system wherein the polyolcomponent is divided into two portions, one containing the tin catalystand the other containing the carboxy functional siloxane mold releaseagent. A second method of overcoming the problems with the use ofcarboxy functional siloxanes is disclosed in U.S. Pat. No. 4,420,570wherein the tin catalyst is blended with the polyisocyanate component,while the carboxy functional siloxane is blended with the polyolcomponent in order to keep them separate.

In a third solution to the problem, U.S. Pat. No. 4,396,729 disclosesreplacing the conventional high molecular weight polyol with an aminatedpolyol. Since no hydroxyl groups are present, it is not necessary to usean organo metallic catalyst and, thus, these catalysts are not presentto interact with the carboxy functional siloxanes. U.S. Pat. No.4,472,341 discloses a fourth solution to this problem wherein the acidgroup of the carboxy functional siloxane is chemically derivatized toform a new compound which does not interact with the organo metalliccatalyst.

Even though these solutions presented in the above-identified patents dosolve the problem of the interaction between the carboxy functionalsiloxane and the tin catalyst, there are disadvantages to thesesolutions. For example, it is very difficult to accurately meter threestreams and, thus, this system is not used commercially. The addition oftin catalysts to the polyisocyanate component reduces the storagestability of this component, while the use of amino polyethers excludesthe use of hydroxyl group-containing reactants. Finally, the formationof derivatives of the carboxy functional siloxanes reduces the moldrelease effects of these compounds.

Accordingly, it is an object of the present invention to provide moldrelease compositions which are storage stable, provide multiple releasesand do not require special reactants or apparatus for processing. It isalso an object of the present invention to provide mold releasecompositions which do not degrade the properties normally associatedwith these optionally cellular polyurethane elastomers. Surprisingly,these objects may be achieved in accordance with the invention describedhereinafter.

SUMMARY OF THE INVENTION

The present invention is directed to a process for the production ofoptionally cellular, polyurethane or polyurea elastomers or optionallycellular, rigid structural polyurethanes or polyureas by reacting areaction mixture containing

(i) a polyisocyanate,

(ii) a high molecular weight polymer having at least twoisocyanate-reactive groups and having a molecular weight of 400 to about10,000,

(iii) about 5 to 50% by weight, based on the weight of component (ii) ofa chain-extender having at least two isocyanate-reactive groups and

(iv) about 0.05 to 10 weight percent, based on the weight of components(ii) and (iii) of a salt based on a carboxy functional siloxane and anamidine group-containing compound of the formula ##STR2## wherein R₁, R₂and R₃ are straight or branched, saturated or unsaturated hydrocarbonchains having up to 30 carbon atoms which may optionally be substitutedby ether groups, ester groups, amide groups or amidine groups and mayalso optionally be terminated by isocyanate-reactive groups such ashydroxyl or amino groups,

R₄ corresponds to the definition of R₁, R₂ and R₃, but may additionallyrepresent an aromatic substituent having 6 to 15 carbon atoms or mayrepresent the group --NR₂ R₃ and

R₁, R₂, R₃ and R₄ may, with one or both of the amidine nitrogens, alsoform a heterocyclic ring.

The present invention is also directed to the amidine group-containingsalt (iv) and to an isocyanate-reactive composition based on components(ii), (iii) and (iv).

DETAILED DESCRIPTION OF THE INVENTION

The mold release agent mixture may also contain

(v) an optionally alkoxylated fatty amide or a salt of a aliphaticcarboxylic acid and a primary amine or a primary, secondary or tertiaryamine containing an amide or an ester group and also

(vi) a tertiary amine-containing, isocyanate reactive compoundcorresponding to the formula ##STR3## wherein R₆ is a straight orbranched alkyl radical having 1 to 4 carbon atoms,

R₇ is an alkylene, dialkylene ether or polyether diradical,

R₈ is a straight or branched, saturated or unsaturated, hydrocarbonchain having up to 30 carbon atoms which may optionally be substitutedby ether, ester or amide groups, x is independently a number of fromabout 1 to 50, and y and z are independently 0, 1 or 2 with the provisothat y +z must be at least 1.

The mold release compositions of the present invention are suitable foruse with either flexible or rigid, optionally cellular, polyurethane orpolyurea elastomers. The molded articles may possess variouscombinations of these properties such as rigid, non-cellular elastomersor flexible, cellular products for use, e.g., as shoe soles."Polyurethanes" as defined throughout this application are polyadditionproducts wherein urethane groups and optionally urea groups are formedduring the RIM process according to the invention. "Polyureas" aredefined as polyaddition products wherein only urea groups are formedduring the RIM process according to the invention.

In accordance with the present invention it has been discovered that theprevious difficulties regarding the compatibility of the carboxyfunctional siloxanes with tin catalysts may be overcome by forming asalt of the siloxanes with a compound containing an amidine group asdiscussed hereinafter. In addition, it has been found that the number ofreleases may be even further increased, especially in rigid systems, byincorporating the salts discussed hereinafter and disclosed in U.S. Pat.No. 3,726,952. Finally, it has been discovered that the ease of releaseof the first few releases may be improved by adding specific tertiaryamine group-containing compounds to be discussed hereinafter.

Suitable polyisocyanates for use in the present invention are thealiphatic, cycloaliphatic, araliphatic, aromatic and heterocyclicpolyisocyanates which are known and described for example by W. Siefkenin Justus Liebigs Annalen der Chemie, 562, pages 75-136. Specificexamples include ethylene diisocyanate, 1,4-tetramethylene diisocyanate,1,6-hexamethylene diisocyanate, 1,12-dodecane diisocyanate,cyclobutane-1,3-diisocyanate, cyclohexane-1,3- and -1,4-diisocyanate andmixtures thereof,1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclo-hexane (isophoronediisocyanate or IPDI), 2,4- and 2,6-hexahydrotoluylene diisocyanate andmixtures thereof, hexahydro-1,3- and/or -1,4-phenylene diisocyanate,perhydro-2,4'- and/or -4,4'-diphenyl methane diisocyanate, 1,3- and1,4-phenylene diisocyanate, 2,4- and 2,6-toluylene diisocyanate andmixtures thereof, diphenyl methane 2,4'- and/or 4,4'-diisocyanate,naphthylene 1,5-diisocyanate, triphenyl methane-4,4',4"-triisocyanateand polyphenyl polymethylene polyisocyanates of the type obtained bycondensing aniline with formaldehyde, followed by condensation.

It is preferred to use the readily available polyisocyanates such as2,4- and 2,6-toluylene diisocyanate and mixtures of these isomers,polyphenyl polymethylene polyisocyanates of the type obtained bycondensing aniline with formaldehyde, followed by phosgenation, andpolyisocyanates containing carbodiimide groups, urethane groups,allophanate groups, isocyanurate groups, urea groups or biuret groups.Particularly preferred are the liquid derivatives of 4,4'-diphenylmethane diisocyanate (MDI) which may be liquefied inter alia byintroducing carbodiimide groups, blending with 2,4'-diphenyl methanediisocyanate or by introducing urethane groups. Especially preferred arethe liquefied derivatives of MDI prepared by reacting MDI with 0.1 to0.3 mols of a polypropylene glycol having a molecular weight of up toabout 700, in particular, dipropylene glycol, tripropylene glycol ormixtures thereof as disclosed, for example, in U.S. Pat. No. 3,644,457.

Also suitable for use as the polyisocyanate component areisocyanate-terminated prepolymers based on the above-mentionedpolyisocyanates and the isocyanatereactive compounds, preferablyhydroxyl compounds, disclosed hereinafter for use in accordance with thepresent invention. Prepolymers of this type are disclosed in U.S. Pat.No. 4,374,210. The prepolymers are preferably based on the polyether orpolyester polyols disclosed hereinafter and, optionally, the lowmolecular weight, hydroxyl group-containing chain extenders which arealso disclosed hereinafter. Blends of any of the previously disclosedpolyisocyanates may also be used in accordance with the presentinvention.

Other suitable reactants for preparing the polyurethane elastomers ofthe present invention include compounds containing at least twoisocyanate-reactive groups. These compounds may be divided into twogroups, high molecular weight compounds having a molecular weight of 400to about 10,000 and low molecular weight compounds, i.e. chainextenders, having a molecular weight of 62 to 399. Examples of suitablehigh molecular weight compounds include the polyesters, polyethers,polythioethers, polyacetals and polycarbonates containing at least 2,preferably 2 to 8 and most preferably 2 to 4 isocyanate-reactive groupsof the type known for the production of polyurethanes.

The high molecular weight polyethers suitable for use in accordance withthe invention are known and may be obtained, for example, bypolymerizing epoxides such as ethylene oxide, propylene oxide, butyleneoxide, tetrahydrofuran, styrene oxide or epichlorohydrin in the presenceof BF₃ or by chemically adding these epoxides, preferably ethylene oxideand propylene oxide, in admixture or successively to componentscontaining reactive hydrogen atoms such as water, alcohols or amines.Examples of alcohols and amines include the low molecular weight chainextenders set forth hereinafter, 4,4'-dihydroxy diphenyl propane,sucrose, aniline, ammonia, ethanolamine and ethylene diamine. It ispreferred to use polyethers which contain substantial amounts of primaryhydroxyl groups in terminal positions (up to 90% by weight, based on allof the terminal hydroxyl groups present in the polyether). Polyethersmodified by vinyl polymers, of the type formed, for example, bypolymerizing styrene or acrylonitrile in the presence of polyether (U.S.Pat. Nos. 3,383,351; 3,304,273; 3,523,093; and 3,110,695; and GermanPat. No. 1,152,536), are also suitable, as are polybutadienes containingOH groups.

In addition, polyether polyols which contain high molecular weightpolyadducts or polycondensates in finely dispersed form or in solutionmay be used. Such modified polyether polyols are obtained whenpolyaddition reactions (e.g. reactions between polyisocyanates and aminofunctional compounds) or polycondensation reactions (e.g., betweenformaldehyde and phenols and/or amines) are directly carried out in situin the polyether polyols.

Suitable examples of high molecular weight polyesters include thereaction products of polyhydric, preferably dihydric alcohols(optionally in the presence of trihydric alcohols), with polyvalent,preferably divalent, carboxylic acids. Instead of using the freecarboxylic acids, it is also possible to use the correspondingpolycarboxylic acid anhydrides or corresponding polycarboxylic acidesters of lower alcohols or mixtures thereof for producing thepolyesters. The polycarboxylic acids may be aliphatic, cycloaliphatic,aromatic, and/or heterocyclic and may be unsaturated or substituted, forexample, by halogen atoms. The polycarboxylic acids and polyols used toprepare the polyesters are known and described for example in U.S. Pat.Nos. 4,098,731 and 3,726,952, herein incorporated by reference in theirentirety. Suitable polythioethers, polyacetals, polycarbonates and otherpolyhydroxyl compounds are also disclosed in the aboveidentified U.S.patents. Finally, representatives of the many and varied compounds whichmay be used in accordance with the invention may be found for example inHigh Polymers, Volume XVI, "Polyurethanes, Chemistry and Technology," bySaunders-Frisch, Interscience Publishers, New York, London, Vol. I,1962, pages 32-42 and 44-54, and Volume II, 1964, pages 5-6 and 198-199;and in Kunststoff-Handbuch, Vol. VII, Vieweg-Hochtlen, Carl HanserVerlag, Munich, 1966, pages 45-71.

Suitable aminopolyethers which may be used in accordance with thepresent invention as high molecular weight compounds (the molecularweight is always the average molecular weight which may be calculatedfrom the functionality and the content of isocyanate-reactive groups)are those wherein at least about 30 and preferably about 60 to 100equivalent % of the isocyanate-reactive groups are primary and/orsecondary (preferably primary) aromatically or aliphatically (preferablyaromatically) bound amino groups and the remainder are primary and/orsecondary aliphatically bound hydroxyl groups.

In these compounds, the terminal residues carrying the amino groups mayalso be attached to the polyether chain by urethane or ester groups.These "aminopolyethers" are prepared by methods known per se. Forexample, polyhydroxypolyethers such as polypropylene glycol ethers maybe aminated by reaction with ammonia in the presence of Raney nickel andhydrogen (BE-PS No. 634,741). U.S. Pat. No.3,654,370 describes theproduction of polyoxyalkylene polyamines by reaction of thecorresponding polyol with ammonia and hydrogen in the presence of anickel, copper, chromium catalyst. DE-PS No. 1,193,671 describes theproduction of polyethers containing terminal amino groups byhydrogenation of cyanoethylated polyoxypropylene ethers. Other methodsfor the production of polyoxyalkylene (polyether) amines are describedin U.S. Pat. No.3,155,728, U.S. Pat. No.3,236,895 and FR-PSNo.1,551,605. The production of polyethers containing terminal secondaryamino groups is described, for example, in FR-PS No. 1,466,708.

Polyhydroxypolyether of relatively high molecular weight may beconverted into the corresponding anthranilic acid esters by reactionwith isatoic acid anhydride, as described, for example, in DE-OS Nos.2,019,432 and 2,619,840 and in U.S. Pat. Nos. 3,808,250, 3,975,428 and4,016,143. Polyethers containing terminal aromatic amino groups areformed in this way.

According to DE-OS No. 2,546,536 and U.S. Pat. No. 3,865,791, relativelyhigh molecular weight compounds containing terminal amino groups areobtained by reaction of NCO prepolymers based on polyhydroxypolyetherswith enamines, aldimines or ketamines containing hydroxyl groups andsubsequent hydrolysis.

It is preferred to use amino polyethers obtained by hydrolysis ofcompounds containing terminal isocyanate groups, for example inaccordance with DE-OS No. 2,948,419 or U.S. Pat. No. 4,515,923, hereinincorporated by reference in its entirety. In this process, polyethersmost preferably containing 2 to 4 hydroxyl groups are reacted withpolyisocyanates to form NCO prepolymers and, in a second step, theisocyanate groups are converted by hydrolysis into amino groups.

The "aminopolyethers" used in accordance with the invention are oftenmixtures of the compounds mentioned by way of example and (on astatistical average) most preferably contain 2 to 4 terminalisocyanate-reactive groups. In the process according to the invention,the "aminopolyethers" may be used in admixture withpolyhydroxypolyethers free from amino groups.

In accordance with the present invention, the high molecular weightcompounds are used in admixture with up to about 95% by weight,preferably up to about 50% by weight, more preferably about 8 to 30% byweight and most preferably about 12 to 26% by weight, based on the totalquantity of the high molecular weight compounds, of the low molecularweight chain extenders. Examples of suitable hydroxyl group-containingchain extenders include ethylene glycol, 1,2- and 1,3-propane diol,1,3-, 1,4- and 2,3-butane diol, 1,6-hexane diol, 1,10-decane diol,diethylene glycol, triethylene glycol, tetraethylene glycol, dipropyleneglycol, tripropylene glycol, glycerol and trimethylol propane.

Other suitable chain extenders include aromatic polyamines, preferablydiamines, having molecular weights of less than 400, especially thesterically hindered aromatic diamines which contain at least one linearor branched alkyl substituent in the ortho-position to the first aminogroup and at least one, preferably two linear or branched alkylsubstituents containing from 1 to 4, preferably 1 to 3, carbon atoms inthe ortho-position to a second amino group. These aromatic diaminesinclude 1-methyl-3,5-diethyl- 2,4-diamino benzene,1-methyl-3,5-diethyl-2,6-diamino benzene, 1,3,5-trimethyl-2,4-diaminobenzene, 1,3,5-triethyl-2,4-diamino benzene,3,5,3',5'-tetraethyl-4,4'-diamino diphenylmethane,3,5,3',5'-tetraisopropyl-4,4'-diamino diphenylmethane,3,5-diethyl3',5'-diiso-propyl-4,4'-diamino diphenylmethane,3,5-diethyl-5,5'-diisopropyl-4,4'-diamino diphenylmethane,1-methyl-2,6-diamino-3-isopropylbenzene and mixtures of the abovediamines. Most preferred are mixtures of1-methyl-3,5-diethyl-2,4-diamino benzene and1-methyl-3,5-diethyl-2,6-diamino benzene in a weight ratio between about50:50 to 85:15, preferably about 65:35 to 80:20.

In addition, aromatic polyamines may be used in admixture with thesterically hindered chain extenders and include, for example, 2,4- and2,6-diamino toluene, 2,4'- and/or 4,4'-diamino-diphenyl-methane, 1,2-and 1,4-phenylene diamine, naphthalene-1,5-diamine andtriphenylmethane-4,4',4"-triamine. The difunctional and polyfunctionalaromatic amine compounds may also exclusively or partly containsecondary amino groups such as 4,4'-di-(methylamino)-diphenylmethane or1-methyl-2-methylamino-4-amino-benzene. Liquid mixtures of polyphenylpolymethylene-polyamines, of the type obtained by condensing anilinewith formaldehyde, are also suitable. Generally, the nonstericallyhindered aromatic diamines and polyamines are too reactive to providesufficient processing time in a RIM system. Accordingly, these diaminesand polyamines should generally be used in combination with one or moreof the previously mentioned sterically hindered diamines or hydroxylgroup-containing chain extenders.

The mold release compositions to be used in combination with thepreviously described reactants for forming polyurethane elastomers,include as a principle component, a salt formed from a carboxyfunctional siloxane such as disclosed in U.S. Pat. No. 4,076,695, hereinincorporated by reference, and a compound containing an amidine group ofthe following formula ##STR4## wherein R₁, R₂ and R₃ are straight orbranched, saturated or unsaturated hydrocarbon chains having up to 30,preferably up to 22 carbon atoms which may optionally be substituted byether groups, ester groups, amide groups or amidine groups and may alsooptionally be terminated by isocyanate-reactive groups such as hydroxylor amino groups.

R₄ corresponds to the definition of R₁, R₂ and R₃, but may additionallyrepresent an aromatic substituent having 6 to 15 carbon atoms or mayrepresent the group --NR₂ R₃ and

R₁, R₂, R₃ and R₄ may, with one or both of the amidine nitrogens, alsoform a heterocyclic ring.

Suitable examples of carboxy functional siloxanes are disclosed in U.S.Pat. No. 4,076,695 and include Dow Corning's Q2-7119 which is apolysiloxane containing substituents corresponding to the formula

    --CH.sub.2 CH.sub.2 SCH.sub.2 COOH                         (II)

Examples of suitable amidine group-containing compounds includediazabicycloundecene, the tetraalkyl guanidines such as tetramethylguanidine, cyclic amidines of the above formula I wherein R₁ and R₂ forma heterocyclic ring such as compounds corresponding to the formula##STR5## wherein R₄ contains a saturated or unsaturated fatty grouphaving 8 to 30, preferably 8 to 22 carbon atoms such as1-heptadec-8-7-enyl or preferably 1-heptadecyl and R₃ is as definedabove, but may also contain an additional amidine group. Commercialexamples of amidine group containing compounds corresponding to formulaIII are Monazoline O available from Mona Industries, wherein R₄ is1-heptadec-8-7-enyl and R₃ is hydroxy ethyl; Monazoline S available fromMona Industries, wherein R₄ is 1-heptadecyl and R₃ is hydroxy ethyl;Varisoft 475 available from Sherex Chemical, wherein R₄ is a mixture ofsaturated and unsaturated hydrocarbons and R₃ corresponds to the formula##STR6## wherein R₅ corresponds to R₄ ; and Monazoline B-219 availablefrom Mona Industries, wherein R₄ is 1-heptadecyl and R₃ corresponds tothe formula ##STR7##

A further ingredient which assists in compatibilizing the amidine groupcontaining salt in the polyol component of the present invention,especially in rigid polyurethane elastomers, is preferably a salt of analiphatic carboxylic acid and a primary amine or a primary, secondary ortertiary amine containing an amide or an ester group. These salts aredisclosed in U.S. Pat. No. 3,726,952, herein incorporated by referencein its entirety, at column 5, line 22 through column 6, line 55. Apreferred salt is the oleic acid or tall oil fatty acid salt of theamide group containing amine obtained by reacting N-diethylaminopropylamine with oleic acid or tall oil fatty acid. Also suitable arefatty amides such as oleic acid amide, preferably alkoxylated fattyamides and most preferably ethoxylated fatty amides such as ethoxylatedoleic acid amide. However, the fatty amides or their derivatives are notas preferred as the above described salts from U.S. Pat. No. 3,726,952.

An optional additive which may be included in the mold releasecomposition according to the present invention is a tertiary aminecontaining, isocyanate reactive compound corresponding to the formula##STR8## wherein R₆ is a straight or branched alkyl radical having 1 to4 carbon atoms, preferably methyl,

R₇ is an alkylene, dialkylene ether or polyether diradical which has amolecular weight of up to 5000, preferably less than 400, morepreferably less than 100, and most preferably R₇ is a C₂ -C₃ alkyleneradical, R₈ is a straight or branched, saturated or unsaturatedhydrocarbon chain having up to 30, preferably up to 22 carbon atomswhich may optionally be substituted by ether, ester or amide groups,

x is independently a number of from about 1 to 50, preferably about 1 to20, more preferably about 1 to 5 and most preferably about 1 to 3 and

y and z are independently 0, 1 or 2 with the proviso that y+z must be atleast 1.

Examples of these compounds include an ethylene diamine-based polyetherpolyol (supplied as Multranol 4050 from Mobay) and more preferably, acompound (Ethoduomeen T-13 available from Akzo Chemie) of the formula##STR9## wherein R₈ is defined as above.

The amidine group containing compound should be present in an amount ofabout 0.05 to 10, preferably about 0.1 to 5 and most preferably about0.2 to 1.0 weight percent, based on the weight of the polyol component.The optional release agent should be present in an amount of up to about10, preferably up to about 5 and most preferably about 1 to 5 weightpercent, based on the weight of the polyol component. Finally, thetertiary amine containing, isocyanate-reactive compound should bepresent in an amount of up to about 10, preferably up to about 8.5, morepreferably about 2 to 6 weight percent, based on the weight of thepolyol component.

Other additives which may be used in the molding compositions of thepresent invention include catalysts, especially tin(II) salts ofcarboxylic acids, dialkyl tin salts of carboxylic acids, dialkyl tinmercaptides, dialkyl tin dithioesters and tertiary amines. Preferredamong these catalysts are dibutyl tin dilaurate and1,4-diaza-bicyclo-(2,2,2)-octane (triethylene diamine), especiallymixtures of these catalysts. The catalysts are generally used in amountsof about 0.01 to 10%, preferably about 0.05 to 2%, based on the weightof the high molecular weight component.

It is also possible to use surface-active additives such as emulsifiersand foam stabilizers. Examples include N-stearyl-N',N'-bis-hydroxyethylurea, oleyl polyoxyethylene amide, stearyl diethanol amide, isostearyldiethanolamide, polyoxyethylene glycol monoleate, apentaerythritol/adipic acid/oleic acid ester, a hydroxy ethyl imidazolederivative of oleic acid, N-stearyl propylene diamine and the sodiumsalts of castor oil sulfonates or of fatty acids. Alkali metal orammonium salts of sulfonic acid such as dodecyl benzene sulfonic acid ordinaphthyl methane sulfonic acid and also fatty acids such as ricinoleicacid or polymeric fatty acids may also be used as surface-activeadditives.

Suitable foam stabilizers include water-soluble polyether siloxanes. Thestructure of these compounds is generally such that a copolymer ofethylene oxide and propylene oxide is attached to a polydimethylsiloxane radical. Such foam stabilizers are described in U.S. Pat. No.2,764,565. In addition to the catalysts and surface-active agents, otheradditives which may be used in the molding compositions of the presentinvention include known blowing agents, cell regulators, flame retardingagents, plasticizers, dyes, fillers and reinforcing agents such as glassin the form of fibers or flakes or carbon fibers.

The compositions according to the present invention may be molded usingconventional RIM processing techniques and are especially suited forprocessing by the RIM process. In general, two separate streams areintimately mixed and subsequently injected into a suitable mold,although it is possible to use more than two streams. The first streamcontains the polyisocyanate component, while the second stream containsthe polyol component, chain extender, the internal mold release agentmixture and any other additive which is to be included.

The invention is further illustrated but is not intended to be limitedby the following examples in which all parts and percentages are byweight unless otherwise specified.

EXAMPLES Description of Materials

Amidine Salt I

Amidine Salt I was prepared by adding 880.2 parts (12.1) of2-(1-heptadecyl)-3-(2-hydroxyethyl)-2-imidazoline to 6377.4 parts of DowCorning's Q2-7119, a carboxy functional siloxane, at 80° with stirring.When all of the solids had dissolved, the mixture was allowed to cool toroom temperature.

Amidine Salt II

Following the above procedure, Amidine Salt II was prepared from 880.2parts of 2-(1-heptadecyl)-3-(2-hydroxyethyl)-2-imidazoline and 3188.7parts of Dow Corning's Q2-7119.

Amidine Salt III

Following the above procedure, Amidine Salt III was prepared from 440.1parts of 2-(1-heptadecyl)-3-(2-steramidoethyl)-2-imidazoline and 3188.7parts of Dow Corning's Q2-7119.

Amidine Salt IV

Following the above procedure, Amidine Salt IV was prepared from 632parts of 2-(1-heptadecyl)-3- (2-ethoxyformylethoxyethyl)-2-imidazolineand 3611.4 parts of Dow Corning's Q2-7119.

Amidine Salt V

Following the above procedure, Amidine Salt V was prepared from 440.1parts of 2-(1-heptadec-8-7-enyl) 3-(2-hydroxyethyl)-2-imidazoline and3188.7 parts of Dow Corning's Q2-7119.

Amidine Salt VI

Following the above procedure, Amidine Salt VI was prepared from 138.2parts of 1,8-diazabicyclo[5.4.0]undec-7-ene and 2500 parts of DowCorning's Q2-7119.

Amidine Salt VII

Following the above procedure, Amidine Salt VII was prepared from 180parts of 2-(1-heptadecyl)-3-(2-hydroxyethyl)-2-imidazoline and 2820parts of Dow Corning's Q2-7119.

POLYOL A--a 45/55 mixture of glycerine initiatedpoly(oxyalkylene)-polyether triols, one having a hydroxyl number of 28and based on 82.5% propylene oxide tipped with 17.5% ethylene oxide andthe other having a hydroxyl number of 1058 and based on 100% propyleneoxide.

POLYOL B--a propylene glycol initiated polyether diol based on 80%propylene oxide tipped with 20% ethylene oxide and having an OH numberof 28.

POLYOL C--a dispersion of 20% of a TDI/hydrazine adduct prepared in 80%of a glycerine-initiated polyether triol based on 83% propylene oxidetipped with 17% ethylene oxide and having an OH number of 35.

POLYOL D--a polyester polyol having a molecular weight of 3,000, afunctionality of 2.04 and based on the reaction product of 54.4 parts ofadipic acid, 12.3 parts of 1,4-butane diol, 48.4 parts of tetraethyleneglycol and 0.3 parts of trimethylol propane.

POLYOL E--a polyester polyol having a molecular weight of 2,000 andbased on adipic acid and a mixture of ethylene glycol and butyleneglycol in a 1:1 molar ratio.

POLYOL F--A glycerine initiated poly(oxyalkylene)polyether triol havinga hydroxyl number of 28 and based on 86% propylene oxide tipped with 14%ethylene oxide.

POLYOL G--a polypropylene glycol having a hydroxyl number of 56.

POLYOL H--a glycerine initiated polypropylene triol having a hydroxylnumber of 56.

POLYOL I--a TMP/water-initiated (4.5:1 weight ratio) hydroxypolypropylene having an OH number of 56 and a functionality of 2.4.

POLYOL J--a glycerine-initiated poly(oxyalkylene)polyether triol havingan OH number of 35 and prepared from 4.6% propylene oxide, followed by4.7% ethylene oxide, followed by 82.3% propylene oxide and, finally,8.4% ethylene oxide.

POLYOL K--a mixture of two parts of Polyol I with one part of Polyol J.

SURFACTANT A--a commercial silicone surfactant supplied as DC-193 by DowCorning.

SURFACTANT B--a commercial silicone surfactant supplied as L-5307 byUnion Carbide.

SURFACTANT C--a commercial silicone surfactant supplied as Tegosioxin20,000 by Goldschmidt.

SURFACTANT D--a commercial silicone surfactant supplied as L-5430 byUnion Carbide.

COMBUSTION MODIFIER A--a neutral cyclic phosphorus ester containing 21%phosphorus available as Antiblaze 19 from Albright and Wilson.

TIN CATALYST I--dibutyl tin dilaurate supplied as Thermalite 12 by MTChemical or as Fomrez SUL-4 by Witco.

TIN CATALYST II--dimethyl tin mercaptide supplied as Fomrez UL-22 byWitco.

AMINE CATALYST I--N,N-dimethylcyclohexylamine supplied as Polycat 8 byAir Products.

AMINE CATALYST II--triethylene diamine, supplied as a 3% solution in aglycol carrier as Dabco 33LV by Air Products or as Thancat TD-33 byTexaco.

AMINE CATALYST III--The reaction product of1,8-diazabicyclo[5.4.0]undec-7-ene and 2-ethylhexanoic acid supplied asPolycat SA-102 by Air Products.

AMINE CATALYST IV--1,8-diazabicyclo[5.4.0]undec-7-ene.

BLOWING AGENT A--fluorotrichloromethane, supplied as Freon R-11 byDuPont or Isotron 11 by Pennwalt.

POLYOL RESIN A--a blend of 91.5 parts Polyol A, 3 parts Surfactant A,0.25 parts Tin Catalyst II, 1.5 parts Amine Catalyst I, 19 partsCombustion Modifier A and 4 parts Blowing Agent A.

POLYOL RESIN B--a blend of 91.5 parts Polyol A, 3 parts Surfactant A,0.25 parts Tin Catalyst I, 1.5 parts Amine Catalyst I, 19 partsCombustion Modifier A and 8 parts Blowing Agent A.

POLYOL RESIN C--a blend of 68.40 parts Polyol B, 13.52 parts Polyol C,7.22 parts 1,4-butane diol, 0.76 parts Amine Catalyst II, 0.03 parts TinCatalyst I, 0.11 parts Surfactant B, 0.09 parts Surfactant C, 7.01 partsBlowing Agent A and 0.16 parts water.

Polyisocyanate I--a liquid semi-prepolymer prepared by reacting4,4'-diphenylmethane diisocyanate and tripropylene glycol in a molarratio of about 5:1 to provide a product having an NCO content of about23% and a viscosity at 25° C. of 725±175 cps.

Polyisocyanate II--an aniline/formaldehyde condensation productcontaining 4,4'-diphenylmethane diisocyanate and about 50% of higherfunctionality homologs, having an NCO content of about 31.5% and aviscosity at 25° C. of 200 cps.

Polyisocyanate III--a mixture having an overall isocyanate content of19% and based on 94% by weight of an isocyanate-terminated prepolymerprepared from 4,4'-diphenylmethane diisocyanate and Polyol V and 6% ofcarbodiimidized 4,4'-diphenylmethane diisocyanate having an isocyanateequivalent weight of 143.

Polyisocyanate IV--an aniline/formaldehyde condensation productcontaining 42% 4,4'-diphenylmethane diisocyanate, 17% of the2,4'-isomer, 2% of the 2,2'-isomer and the remainder higher functionalhomologs.

ISOCYANATE PREPOLYMER I--an isocyanate-terminated prepolymer having anNCO content of 18.3% prepared from 47.0 parts of 4,4'-diphenylmethanediisocyanate, 12.0 parts of Polyisocyanate IV and 41.0 parts of PolyolG.

ISOCYANATE PREPOLYMER II--an isocyanate-terminated prepolymer having anNCO content of 17.9% prepared from 47.0 parts of4,4'-diisocyanatodiphenylmethane, 11.8 parts of Polyisocyanate IV and41.2 parts of Polyol H.

ISOCYANATE PREPOLYMER III--an isocyanate-terminated prepolymer having anNCO content of 17.6% and prepared from 44.9 parts of4,4'-diisocyanatodiphenylmethane, 11.2 parts of Polyisocyanate IV and43.9 parts of Polyol F.

AMINE-TERMINATED POLYETHER I--1 mol of Polyol K was reacted with 2 molsof 2,4-toluylene diisocyanate to form an isocyanate-terminatedprepolymer and the terminal isocyanate groups were subsequentlyconverted to amine groups.

SURFACE ACTIVE AGENT A--the tall oil salt of the amide group-containingcompound obtained by reacting N,N-dimethylaminopropylamine with talloil.

SURFACE ACTIVE AGENT B--the reaction product of oleic acid amide with 7moles of ethylene oxide.

SURFACE ACTIVE ACENT C--oleic acid amide.

AMINE INITIATED POLYOLI--N,N',N'-tris(2-hydroxyethyl)-N-tallow-1,3-diamino-propane.

AMINE INITIATED POLYOL II--the 1:1 molar salt of Amine Initiated PolyolI with tall oil.

AMINE INITIATED POLYOL III--propoxylated ethylene diamine (OH number630).

AMINE INITIATED POLYOL IV--the 1:1 molar salt of Amine Initiated PolyolIII with tall oil.

CHAIN EXTENDER I--a commercial preparation of diethyl toluene diamine(DETDA) which is an isomeric mixture of 1-methyl-3,5-diethyl-2,4-diaminobenzene and 1-methyl-3,5-diethyl-2,6-diamino benzene in a ratio ofbetween 65:35 and 80:20.

CHAIN EXTENDER II--a tetrol having an OH number of 560 and prepared frompentaerythritol and propylene oxide available from BASF as PEP-450.

SILOXANE I--a carboxy functional siloxane available from Dow Corning asQ2-7119.

EXAMPLES 1-24

Examples 1-24 were conducted on an HK-100 (available from Hennecke) RIMmachine under the following conditions:

    ______________________________________                                        Mixhead type - 10 millimeter chamber, two-component                           (available from Krauss-Maffei)                                                ______________________________________                                        Weight ratio, polyisocyanate/resin blend                                                                130/100                                             Injection rate, pounds per second                                                                       1                                                   Mold temperature °F.                                                                             160                                                 Part weight, pound        1.2                                                 Resin blend, density g/cc 0.80                                                Material temperature °F.                                               Polyisocyanate Component  95                                                  Resin Component           95                                                  Mix pressures, psi                                                            Polyisocyanate Component  2500                                                Resin Component           2500                                                Demold time, minutes      2                                                   ______________________________________                                    

The examples were conducted using the components set forth in Tables Iand II to produce a 12"×12"×1/4 test panel. Each example was continuedto determine the number of release before the part became difficult toremove or when the parts became destroyed or damaged at demold becauseof the adherence of the part to the mold surface. In Table II (Examples11-24) the wax base coat set forth in Table I was used in all of theexamples. The polyisocyanate component is a 50/50 blend ofPolyisocyanate I and II. The external wax release agent was Chem-TrendCT 2001; the external soap release agent was Chem-Trend RCTW 2006.

                                      TABLE I                                     __________________________________________________________________________              Example                                                                               3                                                                     1   2   (Comparison)                                                                         4   5   6   7   8   9   10                           __________________________________________________________________________    Polyol Resin                                                                            B,96.5                                                                            B,91.5                                                                            A,100.0                                                                              A,91.5                                                                            A,91.5                                                                            A,91.5                                                                            A,91.5                                                                            A,91.5                                                                            A,91.5                                                                            A,91.5                       Amidine Salt                                                                            I,3.5                                                                             I,3.5                                                                             --     I,3.5                                                                             I,3.5                                                                             1,3.5                                                                             V,3.5                                                                             V,3.5                                                                             VI,3.5                                                                            VI,3.5                       Amine Initiated                                                                             I,5 --     I,5 I,5 I,5 I,5 I,5 I,5 I,5                          Polyol                                                                        Surface Active                                                                          A,6 A,6 --     --  A,6 A,6 A,6 A,6 A,6 A,6                          Agent                                                                         External Base Coat                                                                      Wax Wax Wax    Wax Wax Soap                                                                              Wax Soap                                                                              Wax Soap                         Number of Releases                                                                      40  40+ 5      19  40+ 30+ 40+ 15  40+ 12                           __________________________________________________________________________     .sup.1 Contained Tin Catalyst I instead of II                            

                                      TABLE II                                    __________________________________________________________________________              Example                                                                       11 12 13 14 15  16 17 18 19 20 21 22  23  24                        __________________________________________________________________________    Polyol Resin A                                                                          95.75                                                                            93.2                                                                             93.2                                                                             93.6                                                                             86.5                                                                              88.5                                                                             91.5                                                                             91.5                                                                             91.5                                                                             91.5                                                                             91.5                                                                             91.5                                                                              91.5                                                                              91.5                      Amidine Salt                                                                            I,1.8                                                                            I,1.8                                                                            I,1.8                                                                            1,2.6                                                                            II,8.6                                                                            II,5                                                                             I,3.5                                                                            I,3.5                                                                            I,3.5                                                                            I,3.5                                                                            I,3.5                                                                            III3.5                                                                            VII,3.5                                                                           IV 3.5                    Amine Initiated                                                                         I,2.5                                                                            I,5                                                                              I,3.8                                                                            I,3.8                                                                            I,5 I,5                                                                              III,5                                                                            II,5                                                                             IV,5                                                                             I,5                                                                              I,5                                                                              I,5 I,5 I,5                       Polyol                                                                        Surface Active                                                                          A,6                                                                              A,6                                                                              A,6                                                                              A,6                                                                              A,6 A,6                                                                              A,6                                                                              -- -- B,6                                                                              C,6                                                                              A,6 A,6 A,6                       Agent                                                                         Number of Releases                                                                      10 40 40 20 70  25 40 19 15 19 8  20  40  40                        __________________________________________________________________________

EXAMPLES 25-29

Examples 25-29 were conducted in a DESMA PSA-70 machine usingPolyisocyanate I as the polyisocyanate component and using the polyolcomponents set forth in Table III. The two components were blended andinjected into a shoe sole mold through a mixhead under low pressure. Thenumber of releases were determined before the part became damaged uponremoval or until there was some adherence of the polyurethane materialto the surface of the mold.

                  TABLE III                                                       ______________________________________                                                   Example                                                                       25    26      27      28    29                                     ______________________________________                                        Polyol Resin C,97.3  C,97.3  C,92.32                                                                             C,90.0                                                                              C,92.32                              Amidine Salt I,2.70  II,2.70 II,2.56                                                                             I,5.0 I,2.56                               Surface Active Agent                                                                       --      --      A,5.12                                                                              A,5.0 A,5.12                               Number of Releases                                                                         24      5       11    13    8                                    ______________________________________                                    

EXAMPLE 30

Following the procedure of Examples 25-29, 86.7 parts of Polyol D, 12.5parts of 1,4-butane diol, 0.43 parts of triethylene diamine, 0.04 partsof Amine Catalyst III, 0.34 parts water and 2.1 parts of Amidine Salt Iwere reacted with an equivalent amount by weight of Polyisocyanate III.Prior to the reaction the molds were cleaned and pretreated withChem-Trend MR 515. Eleven easy releases were obtained and afterreapplication of a light coating of the release agent, an additionalnine easy releases were obtained. The use of a similar formulation whichwas identical in every respect with the above formulation except for thepresence of Amidine Salt I resulted in only two easy releases.

EXAMPLES 31-39

Examples 31-39 were conducted in a Cincinnati-Millicron RIM machineusing a Chevrolet Monte Carlo fascia mold using the materials set forthin Table IV. All of the materials were mixed with the polyol componentexcept for the polyisocyanate. Prior to conducting the examples, themold was treated with Chem-Trend CT 2002, an external mold releaseagent.

                                      TABLE IV                                    __________________________________________________________________________             EXAMPLE                                                                       31  32  33  34  35  36  37  38  39                                   __________________________________________________________________________    Chain Extender I                                                                       18.0                                                                              18.0                                                                              16.5                                                                              16.5                                                                              16.5                                                                              17.64                                                                             17.50                                                                             17.0                                                                              17.7                                 E-9139 Polyol A                                                                        78.85                                                                             76.85                                                                             78.3                                                                              78.12                                                                             80.0                                                                              77.94                                                                             79.35                                                                             76.85                                                                             76.2                                 Amine Initiated                                                                        I,3.0                                                                             III,2.0                                                                           III,2.0                                                                           III,2.0                                                                           --  --  --  --  --                                   Polyol                                                                        Chain Extender II                                                                      --  --  --  --  --  1.96                                                                              --  --  --                                   Siloxane I                                                                             2.5 2.5 2.5 3.0 3.0 1.96                                                                              2.5 3.5 4.5                                  Tin Catalyst                                                                           II,0.65                                                                           II,0.65                                                                           II,0.70                                                                           --  --  II,0.50                                                                           II,0.55                                                                           I,0.15                                                                            II,0.1                               Amine Catalyst                                                                         --  --  --  IV,0.38                                                                           IV,0.50                                                                           --  II,0.1                                                                            IV,0.5                                                                            IV,0.5                               Polyisocyanate I                                                                       52.9                                                                              51.0                                                                              42.0                                                                              49.0                                                                              43.0                                                                              59.0                                                                              51.2                                                                              49.5                                                                              47.5                                 Number of                                                                              11  11  30  32  12  23  13  15  15                                   Releases                                                                      __________________________________________________________________________

EXAMPLES 40-43

Examples 40-43 were conducted on a RIM machine using the formulationsset forth in Table V. The polyol mixture (containing all of thematerials set forth in Table V except for the polyisocyanate) andpolyisocyanate were intensively mixed in a force controlled mix head andrapidly injected into an aluminum mold measuring 30×20×0.4 cm andmaintained at a temperature of 60° C. The mold was treated withChem-Trend CT 2001, a wax external mold release agent, for Examples 42and 43 and the release of the molded parts was excellent. No externalrelease was used in Examples 40 and 41; in Example 40 the release wasexcellent, while in Example 41 the release was fair.

                  TABLE V                                                         ______________________________________                                                     EXAMPLE                                                                       40    41       42      43                                        ______________________________________                                        Amine Terminated                                                                             62.5    62.5     65.5  65.5                                    Polyether I                                                                   Chain Extender I                                                                             30.0    30       30.0  30                                      Amine Initiated Polyol                                                                       III,3.0 I,3.0    --    --                                      Amidine Salt I 3.5     3.5      3.5   3.5                                     Surfactant D   1.0     1.0      1.0   1.0                                     Isocyanate     I,100   I,96.5   II,96.5                                                                             III,96.4                                Prepolymer                                                                    ______________________________________                                    

Although the invention has been described in detail in the foregoing forthe purpose of illustration, it is to be understood that such detail issolely for that purpose and that variations can be made therein by thoseskilled in the art without departing from the spirit and scope of theinvention except as it may be limited by the claims.

What is claimed is:
 1. A process for the production of an optionallycellular, polyurethane or polyurea elastomer or an optionally cellular,rigid structural polyurethane or polyurea by reacting a reaction mixturecomprising(i) a polyisocyanate, (ii) a high molecular weight polymerhaving at least two isocyanate-reactive groups and a molecular weight of400 to about 10,000, (iii) about 5 to 50% by weight, based on the weightof component (ii) of a chain extender having at least twoisocyanate-reactive groups and (iv) about 0.05 to 10% by weight, basedon the weight of components (ii) and (iii), of a salt based on a carboxyfunctional siloxane and an amidine group-containing compound of theformula ##STR10## wherein R₁, R₂ and R₃ are straight or branched,saturated or unsaturated hydrocarbon chains having up to 30 carbon atomswhich may optionally be substituted by ether groups, ester groups, amidegroups or amidine groups and may also optionally be terminated byisocyanate-reactive groups,R₄ corresponds to the definition of R₁, R₂and R₃, but may additionally represent an aromatic substituent having 6to 15 carbon atoms or may represent the group --NR₂ R₃ and R₁, R₂, R₃and R₄ may, with one or both of the amidine nitrogens, also form aheterocyclic ring.
 2. The process of claim 1 wherein the reactionmixture is processed as a one-shot system by the RIM process using anisocyanate index of about 70 to
 120. 3. The process of claim 1 whereinreaction mixture additionally comprises a salt of an aliphaticcarboxylic acid and a primary amine or a primary, secondary or tertiaryamine containing an amide or an ester group.
 4. The process of claim 1wherein said reaction mixture additionally contains a tertiaryamine-containing, isocyanate-reactive compound corresponding to theformula ##STR11## wherein R₆ is a straight or branched alkyl radicalhaving 1 to 4 carbon atoms,R₇ is an alkylene, dialkylene ether orpolyether diradical, R₈ is a straight or branched, saturated orunsaturated hydrocarbon chain having up to 30 carbon atoms which mayoptionally be substituted by ether, ester or amide groups, x isindependently a number of about 1 to 50, y and z are independently 0, 1or 2 with the proviso that y+z must be at least
 1. 5. The process ofclaim 3 wherein said reaction mixture additionally contains a tertiaryamine-containing, isocyanate-reactive compound corresponding to theformula ##STR12## wherein R₆ is a straight or branched alkyl radicalhaving 1 to 4 carbon atoms,R₇ is an alkylene, dialkylene ether orpolyether diradical, R₈ is a straight or branched, saturated orunsaturated hydrocarbon chain having up to 30 carbon atoms which mayoptionally be substituted by ether, ester or amide groups, x isindependently a number of about 1 to 50, y and z are independently 0, 1or 2 with the proviso that y+z must be at least
 1. 6. The process ofclaim 1 wherein said amidine group containing compound corresponds tothe formula ##STR13## wherein R₄ contains a saturated or unsaturatedfatty group and R₃ is as previously defined above.
 7. The process ofclaim 3 wherein said salt is the tall oil fatty acid salt of the amidegroup-containing amine obtained by reacting N-diethylamino-propylaminewith tall oil fatty acid.
 8. A process for the production of anoptionally cellular, polyurethane elastomer or an optionally cellular,rigid structural polyurethane by reacting a reaction mixturecomprising(i) a polyisocyanate, (ii) a high molecular weight polymerhaving at least two isocyanate-reactive and a molecular weight of 400 toabout 10,000, (iii) about 5 to 50% by weight, based on the weight ofcomponent (ii) of a chain extender having at least twoisocyanate-reactive groups and a mold release agent mixture comprising,based on the weight of component (ii) and (iii), (iv) about 0.05 to 10%by weight, of a salt based on a carboxy functional siloxane and anamidine group-containing compound of the formula ##STR14## wherein R₁,R₂ and R₃ are straight or branched, saturated or unsaturated hydrocarbonchains having up to 30 carbon atoms which may optionally be substitutedby ether groups, ester groups, amide groups or amidine groups and mayalso optionally be terminated by isocyanate-reactive groups,R₄corresponds to the definition of R₁, R₂ and R₃, but may additionallyrepresent an aromatic substituent having 6 to 15 carbon atoms or mayrepresent the group --NR₂ R₃ and R₁, R₂, R₃ and R₄ may, with one or bothof the amidine nitrogens, also form a heterocyclic ring, (v) a salt ofan aliphatic carboxylic acid and a primary amine or a primary, secondaryor tertiary amine containing an amide or an ester group and (vi) atertiary amine-containing, isocyanate-reactive compound corresponding tothe formula ##STR15## wherein R₆ is a straight or branched alkyl radicalhaving 1 to 4 carbon atoms,R₇ is an alkylene, dialkylene ether orpolyether diradical, R₈ is a straight or branched, saturated orunsaturated hydrocarbon chain having up to 30 carbon atoms which mayoptionally be substituted by ether, ester or amide groups, x isindependently a number of about 1 to 50, y and z are independently 0, 1or 2 with the proviso that y+z must be at least
 1. 9. The process ofclaim 8 wherein the reaction mixture is processed as a one-shot systemby the RIM process using an isocyanate index of about 70 to
 120. 10. Theprocess of claim 8 wherein said amidine group-containing compoundcorresponds to the formula ##STR16## wherein R₄ contains a saturated orunsaturated fatty group and R₃ is as previously defined above.
 11. Theprocess of claim 8 wherein said salt is a tall oil fatty acid salt ofthe amide group-containing amine obtained by reactingN-diethylaminopropylamine with tall oil fatty acid.
 12. Anisocyanate-reactive composition which comprises(ii) a high molecularweight polymer having at least two isocyanate-reactive groups and amolecular weight of 400 to about 10,000, (iii) about 5 to 50% by weight,based on the weight of component (ii) of a chain extender having atleast two isocyanate-reactive groups and (iv) about 90.05 to 10% byweight, based on the weight of components (ii) and (iii), of a saltbased on a carboxy functional siloxane and an amidine group-containingcompound of the formula ##STR17## wherein R₁, R₂ and R₃ are straight orbranched, saturated or unsaturated hydrocarbon chains having up to 30carbon atoms which may optionally be substituted by ether groups, estergroups, amide groups or amidine groups and may also optionally beterminated by isocyanate-reactive groups,R₄ corresponds to thedefinition of R₁, R₂ and R₃, but may additionally represent an aromaticsubstituent having 6 to 15 carbon atoms or may represent the group --NR₂R₃ and R₁, R₂ R₃ and R₄ may, with one or both of the amidine nitrogens,also form a heterocyclic ring.
 13. The isocyanate-reactive compositionof claim 12 wherein said composition additionally comprises a salt of analiphatic carboxylic acid and a primary amine or a primary, secondary ortertiary amine containing an amide or an ester group.
 14. Theisocyanate-reactive composition of claim 12 wherein said reactionmixture additionally contains a tertiary amine-containing,isocyanate-reactive compound corresponding to the formula ##STR18##wherein R₆ is a straight or branched alkyl radical having 1 to 4 carbonatoms,R₇ is an alkylene, dialkylene ether or polyether diradical, R₈ isa straight or branched, saturated or unsaturated hydrocarbon chainhaving up to 30 carbon atoms which may optionally be substituted byether, ester or amide groups, x is independently a number of about 1 to50, y and z are independently 0, 1 or 2 with the proviso that y+z mustbe at least
 1. 15. The isocyanate-reactive composition of claim 13wherein said reaction mixture additionally contains a tertiaryamine-containing, isocyanate-reactive compound corresponding to theformula ##STR19## wherein R₆ is a straight or branched alkyl radicalhaving 1 to 4 carbon atoms,R₇ is an alkylene, dialkylene ether orpolyether diradical, R₈ is a straight or branched, saturated orunsaturated hydrocarbon chain having up to 30 carbon atoms which mayoptionally be substituted by ether, ester or amide groups x isindependently a number of about 1 to 50, y and z are independently 0, 1or 2 with the proviso that y+z must be at least
 1. 16. Theisocyanate-reactive composition of claim 12 wherein said amidinegroup-containing compound corresponds to the formula ##STR20## whereinR₄ contains a saturated or unsaturated fatty group andR₃ is aspreviously defined above.
 17. The isocyanate-reactive composition ofclaim 13 wherein said reaction mixture additionally contains a tall oilfatty acid salt of an amide group-containing amine obtained by reactingN-diethylamino-propylamine with tall oil fatty acid.
 18. A salt based ona carboxy functional siloxane and an amidine group-containing compoundof the ##STR21## wherein R₁, R₂ and R₃ are straight or branched,saturated or unsaturated hydrocarbon chains having up to 30 carbon atomswhich may optionally be substituted by ether groups, ester groups, amidegroups or amidine groups and may also optionally be terminated byisocyanate-reactive groups,R₄ corresponds to the definition of R₁, R₂and R₃, but may additionally represent an aromatic substituent having 6to 15 carbon atoms or may represent the group --NR₂ R₃ and R₁, R₂, R₃and R₄ may, with one or both of the amidine nitrogens, also form aheterocyclic ring.
 19. The salt of claim 18 wherein said amidinegroup-containing compound corresponds to the formula ##STR22## whereinR₄ contains a saturated or unsaturated fatty group andR₃ is aspreviously defined above.